FAITH-BASED REASONING & THE GLOBAL WARMING DEBATE

1. FAITH-BASED REASONING & THE GLOBAL WARMING DEBATE Katherine K. Hirschboeck, PhDLaboratory of Tree-Ring ResearchUniversity of Arizona

2. OUTLINE • The Title • The Debate • Scientific Background • Addressing the Questions • Faith-Based Reasoning . . . . another perspective

3. THE TITLE: Scientific American editorial: http://www.sciam.com/2001/0601issue/0601rennie.html

4. The New York Times 2-14-02 article by Andrew C.Revkin “Bush Plan Expected to Slow, Not Halt, Gas Emission Rise” Philip E. Clapp, president of the National Environmental Trust, a private lobbying group, criticized this approach, saying: "The president's global warming proposal appears to be another faith-based initiative: we should have faith that major corporations will line up to volunteer cuts in their carbon pollution. That approach has failed for a decade now, since the president's father set up the first voluntary program." Bush announcing newClimate Plan 2-14-2002

5. OUTLINE • The Title • The Debate • Scientific Background • Addressing the Questions • Faith-Based Reasoning . . . . another perspective

6. THE DEBATE QUESTIONS(actually several debates) • (1) Are Greenhouse Gas (GHG) concentrations in the atmosphere increasing due to anthropogenic sources? • (2) Is the Earth’s Temperature Increasing? • (3) Is there a cause and effect relationship between (1) and (2) above? • What are the projections for the future & the consequences of global warming? • What can/should be done about the problem?

7. OUTLINE • The Title • The Debate • Scientific Background • Addressing the Questions • Faith-Based Reasoning . . . . another perspective

8. SCIENTIFIC BACKGROUND • The Radiation / Energy Balance • The Greenhouse Effect & Greenhouse Gases (GHG) • The Enhanced Greenhouse Effect • The Climate System • Detection & Attribution of Change • Consequences & Impacts

9. ENERGY BALANCE DIAGRAM R = (Q + q)(1- a) - Lu + Ld = H + LE + G

10. Longwaves (LW) The Electro-magnetic Spectrum Shortwaves (SW)

11. [Not to scale] Solar short wavesultraviolet (UV), visible Terrestrial long wavesinfrared (IR)

13. Clouds Gas molecules, dust, aerosols ATMOSPHERE

14. SOLAR SHORTWAVE (mostly ultraviolet, visible) SW BEAMED DIRECTLY TO EARTH’S SURFACE WHERE IT IS ABSORBED: Direct solar radiation

15. SW REFLECTED BACK TO SPACE: “Albedo” By clouds By Earth’s surface

16. SW SCATTERED BACK TO SPACE BY ATMOSPHERE: By dust, aerosols, (e.g. from industrial & volcanic emissions), gas molecules, etc.

17. SW SCATTERED DOWN TO EARTH’s SURFACE where it is absorbed Diffuse solar radiation (reaches the surface)

18. SW ABSORBED IN ATMOSPHERE BY GASES, DUST, etc. Absorbed before it ever reaches the surface, e.g. ultraviolet (UV) rays absorbed by stratospheric ozone gas molecules

19. SW ABSORBED In ATMOSPHERE BY CLOUDS & H2O vapor: Clouds can both reflect and absorb solar radiation: low level clouds tend to reflect more

20. TERRESTRIAL LONGWAVES infrared (IR) LW (IR) EMITTED FROM EARTH’S SURFACE ESCAPING TO SPACE THROUGH THE “OUTGOING ATMOSPHERIC WINDOW” not absorbed by the atmosphere

21. IR EMITTED FROM EARTH’S SURFACE BUT ABSORBED IN THE ATMOSPHERE BY GREENHOUSE GASES Greenhouse gas (def) = any gas that absorbs infrared (IR) radiation in the atmosphere

22. IR EMITTED FROM ATMOSPHERE ESCAPING TO SPACE IR energy eventually lost to space after being absorbed by atmosphere

23. IR EMITTED FROM ATMOSPHERE AND RADIATED BACK TO SURFACE WHERE IT IS ABSORBED Principal cause of global warming  IR radiated back to surface to be absorbed again

24. The Greenhouse Effect All together now:

25. + 100% - 30 % - 70 % = thermals + evapotranspiration + storage [DRIVES WEATHER & CLIMATE PRCESSES] ENERGY BALANCE

26. Without any radiative forcing, solar radiation coming to the Earth would continue to be approximately equal to the infrared radiation emitted from the Earth. = in balance Radiative Forcing (def) A change in the balance between incoming solar radiation and outgoing infrared radiation.

27. = out of balance The addition of GREENHOUSE GASES traps an increased fraction of the infrared radiation, radiating it back toward the surface and creating a warming influence = a positive (+) radiative forcing(because incoming solar radiation will exceed outgoing infrared radiation)

28. Multiple Natural & Anthropogenic Forcings COMPONENTS OF THE GLOBAL CLIMATE SYSTEM

29. FEEDBACK MECHANISM (def) A mechanism that connects one aspect of a system to another. The connection can be either amplifying (+ positive feedback) or moderating / self-regulating (- negative feedback). • Climate feedback = • An atmospheric, oceanic, terrestrial, or other process that is activated by climate changes induced by changes in radiative forcing. • Climate feedbacks may increase (+ positive feedback) or diminish (- negative feedback) the magnitude of the direct climate change.

30. A Negative Climate Feedback (self regulating) Earth heats up  Earth radiates more LW out  Earth cools down again - A Positive Climate Feedback (amplifying) Earth heats up snow and ice melt earlier, glaciers diminish  surface reflectivity (albedo) decreases  more Solar SW gets absorbed  Earth heats up MORE +

31. MULTIPLE FEEDBACKS (e.g., snow / ice, water vapor, clouds, etc.)

32. Detection & Attribution of Change Data & Tools Used: • Instrumental measurements • Determining past (paleo) climate from natural archives (e.g. tree rings, ice cores) • Remote sensing of the environment • Modeling

33. CLIMATE CHANGES OF THE PAST via TREE RINGS & other PROXY Records • Calibration of “proxy” record with instrumental climate record • Statistical reconstructions of past temperature and precipitation values • CONVERGENCE of evidence from multiple proxy sources

34. REMOTE SENSING OF THE ENVIRONMENT

35. MODEL RESULTS & PROJECTIONS Latitude-Longitude grid for a typical atmospheric general circulation model (GCM)

37. OUTLINE • The Title • The Debate • Scientific Background • Addressing the Questions • Faith-Based Reasoning . . . . another perspective

38. THE DEBATE QUESTIONS(actually several debates) • (1) Are Greenhouse Gas (GHG) concentrations in the atmosphere increasing due to anthropogenic sources? • (2) Is the Earth’s Temperature Increasing? • (3) Is there a cause and effect relationship between (1) and (2) above? • What are the projections for the future & the consequences of global warming? • What can/should be done about the problem?

39. Greenhouse Gas(def) • Any gas that absorbs infrared (IR) radiation in the atmosphere. • Greenhouse gases include: • water vapor (H2O) • carbon dioxide (CO2) • methane (CH4) • nitrous oxide (N2O) • ozone (O3) • other trace gases such as CFCs, halogenated fluorocarbons (HCFCs), perfluorinated carbons (PFCs), & hydrofluorocarbons (HFCs)

40. Datafrom ice cores Are the GHG’s increasing due to human activities? Carbon Dioxide CO2 CO2 concentrations are rising at an increasing rate; since the Industrial Revolution, higher than any period during the last 10,000 years. More abundant now than at any time during the 400,000 year ice core record

41. Methane CH4 More abundant now than at any time during the 400,000 year ice core record Nitrous Oxide N2O Concentration has increased ~ 13% in past 200 years.

42. GHG’s have different radiative forcing contributions due to their IR absorption properties, relative concentration, and residence times in the atmosphere The contribution from each of the human-made GHG’s to the change in “radiative forcing” (e.g., to warming) from 1980 to 1990. (Based on model results)

43. = out of balance Anthropogenically Enhanced Greenhouse Effect

44. THE DEBATE QUESTIONS(actually several debates) • (1) Are Greenhouse Gas (GHG) concentrations in the atmosphere increasing due to anthropogenic sources? • (2) Is the Earth’s Temperature Increasing? • (3) Is there a cause and effect relationship between (1) and (2) above? • What are the projections for the future & the consequences of global warming? • What can/should be done about the problem?

45. The most comprehensive source of information on Global Climate Change -- the IPCC • The role of the IPCC is to assess the scientific, technical and socio-economic information relevant for the understanding of the risk of human-induced climate change. • It does not carry out new research nor does it monitor climate related data. • It bases its assessment mainly on published and peer-reviewed scientific technical literature.

46. The IPCC has three working groups and a Task Force: Working Group I -- assesses the scientific aspects of the climate system and climate change.Working Group II -- addresses the vulnerability of socio-economic and natural systems to climate change, negative and positive consequences of climate change, and options for adapting to it.Working Group III -- assessesoptions for limiting greenhouse gas emissions and otherwise mitigating climate change.[The Task Force on National Greenhouse Gas Inventories -- oversees the National Greenhouse Gas Inventories Program]

47. IPCC’s “CLIMATE CHANGE 2001” Reports • “Climate change” in IPCC usage refers to any change in climate over time, whether due to natural variability or as a result of human activity. • 122 Coordinating Lead Authors and Lead Authors • 515 Contributing Authors • 21 Review Editors • 420 Expert Reviewers http://www.ipcc.ch/

49. Some of the evidence for an observed change in temperature summarized in the IPCC reports:

50. = warming = cooling